The Influence of Processing Variables on Performance of O/W Emulsion Gels Based on Polymeric Emulsifier (Pemulen...

Area of Science:

• Cosmetic Science
• Polymer Science

Background:

• Pemulen (R) polymers, specifically Acrylates/C10-C30 alkyl acrylates, function as emulsifiers and viscosity enhancers in oil-in-water (o/w) emulsions.
• Understanding processing effects is crucial for optimizing emulsion gel properties.

Purpose of the Study:

• To investigate how mixing equipment, speed, and time influence the viscosity, physical stability, and aesthetic characteristics of o/w emulsion gels.
• To determine optimal processing parameters for Pemulen TR-2 NF based emulsion gels.

Main Methods:

• An experimental design varying mixing speed and time was applied using a laboratory mixer and a disperser.
• Dependent variables included oil phase separation (physical stability) and viscosity at a shear rate of 180 1/s.
• Data were analyzed using multiple regression analysis with a second-order model.

Main Results:

• For laboratory mixer processing, increased mixing speed and time significantly enhanced viscosity linearly.
• Higher mixing energy (speed and time) correlated with improved, though not always statistically significant, physical stability.
• Disperser processing showed no significant influence of variables on viscosity or stability, and resulted in polymer lumps.

Conclusions:

• Laboratory mixers are suitable for processing Pemulen TR-2 NF emulsion gels, with optimal conditions yielding maximal viscosity and stability.
• Dispersers are inappropriate for these emulsions due to the formation of undispersed polymer lumps and lack of process control.
• Processing parameters, particularly mixing intensity, are critical for achieving desired emulsion gel characteristics.